U.S. patent application number 14/793637 was filed with the patent office on 2016-10-06 for touch panel and display device.
The applicant listed for this patent is Shanghai Tianma Micro-Electronics Co., Ltd., Tianma Micro-Electronics Co., Ltd.. Invention is credited to Yingteng ZHAI.
Application Number | 20160291789 14/793637 |
Document ID | / |
Family ID | 53346515 |
Filed Date | 2016-10-06 |
United States Patent
Application |
20160291789 |
Kind Code |
A1 |
ZHAI; Yingteng |
October 6, 2016 |
TOUCH PANEL AND DISPLAY DEVICE
Abstract
A touch panel and a display device are provided according to the
disclosure. The touch panel includes a common electrode and
multiple pixel electrodes, and each of the pixel electrodes is
short-circuited to the common electrode when the touch panel is
powered off. Thus, there is no potential difference between the
pixel electrode in each pixel unit and the common electrode, and
there is no residual charge between the pixel electrode and the
common electrode, after the touch panel is powered off. Therefore,
liquid crystal molecules may be twisted in the case that the touch
panel is powered off, impurity ions inside the liquid crystal
molecules may not be polarized, and may not be attached to an upper
substrate and a lower substrate of a touch panel in a long
term.
Inventors: |
ZHAI; Yingteng; (Shanghai,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shanghai Tianma Micro-Electronics Co., Ltd.
Tianma Micro-Electronics Co., Ltd. |
Shanghai
Shenzhen |
|
CN
CN |
|
|
Family ID: |
53346515 |
Appl. No.: |
14/793637 |
Filed: |
July 7, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/0412 20130101;
G06F 3/04166 20190501; G06F 3/0416 20130101; G06F 3/044
20130101 |
International
Class: |
G06F 3/041 20060101
G06F003/041; G06F 3/044 20060101 G06F003/044 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 1, 2015 |
CN |
201510152694.5 |
Claims
1. A touch panel, comprising a common electrode and a plurality of
pixel electrodes, wherein each of the pixel electrodes is
short-circuited to the common electrode in the case that the touch
panel is powered off.
2. The touch panel according to claim 1, further comprising: at
least one column of pixel electrodes, the common electrode
comprising a plurality of electrode blocks insulated from each
other, and each of the electrode blocks corresponding to a
plurality of pixel electrodes; a plurality of signal lines and a
plurality of data lines, each of the signal lines being connected
to a respective electrode block, and each of the data lines being
connected to the pixel electrodes in the same column; and the data
lines connected to all pixel electrodes corresponding to an
electrode block are short-circuited with the signal line connected
to a same electrode block, in the case that the touch panel is
powered off.
3. The touch panel according to claim 2, wherein each of the
electrode blocks is a touch electrode of the touch panel.
4. The touch panel according to claim 2, further comprising a
short-circuit connection established between the data lines and the
signal lines in the touch panel, in the case that the touch panel
is powered off.
5. The touch panel according to claim 2, further comprising a
plurality of first switches, a plurality of second switches, a
control line and a short-circuit line, and the first switches and
the second switches each comprise a control electrode, a first
electrode and a second electrode; wherein: the control electrodes
of the first switches and the control electrodes of the second
switches are connected to the control line, the control line is
configured to transmit a control signal, and the control signal is
configured to control the first switches and the second switches to
be turned off in the case that the touch panel operates, or to be
turned on in the case that the touch panel is powered off; the
first electrodes of the first switches are connected to the data
lines, and the first electrodes of the second switches are
connected to the signal lines; and the second electrodes of the
first switches are electrically connected to the second electrodes
of the second switches respectively, wherein the first electrode of
each second switch is connected to a signal line connected to an
electrode block, and the first electrode of the respective first
switch is connected to the data line connected to all pixel
electrodes corresponding to the same electrode block.
6. The touch panel according to claim 5, wherein the second
electrodes of the first switches are electrically connected to the
second electrodes of the second switches in the touch panel.
7. The touch panel according to claim 5, wherein the second
electrodes of the first switches are electrically connected to the
second electrodes of the second switches via a short-circuit line,
and the short-circuit line being in a floating state or at a stable
voltage level.
8. The touch panel according to claim 5, wherein the first switch
or the second switch is a transmission gate.
9. The touch panel according to claim 5, wherein the first switch
or the second switch is a transistor.
10. The touch panel according to claim 9, wherein the transistor is
a thin film transistor, the control electrode is a gate, and the
second electrode is a drain in the case that the first electrode is
a source, or the second electrode is a source in the case that the
first electrode is a drain.
11. The touch panel according to claim 9, wherein the transistor is
an MOS transistor, the control electrode is a gate, and the second
electrode is a drain in the case that the first electrode is a
source, or the second electrode is a source in the case that the
first electrode is a drain.
12. The touch panel according to claim 5, wherein the first
switches and the second switches are disposed on a step of the
joint between the touch panel and the driver chip.
13. The touch panel according to claim 2, wherein a pixel electrode
array is consisted of all pixel electrodes in the touch panel, and
extension directions of the data lines and the signal lines are
column directions of the pixel electrode array.
14. The touch panel according to claim 3, further comprising a
short-circuit connection which is established between the data
lines and the signal lines in the touch panel, in the case that the
touch panel is powered off.
15. The touch panel according to claim 3, wherein a pixel electrode
array consists of the pixel electrodes in the touch panel, and
extension directions of the data lines and the signal lines are
column directions of the pixel electrode array.
16. The touch panel according to claim 6, wherein the second
electrodes of the first switches are electrically connected to the
second electrodes of the second switches via a short-circuit line,
and the short-circuited line is in a floating stated or at a stable
voltage level.
17. The touch panel according to claim 6, wherein the first switch
or the second switch is a transmission gate.
18. The touch panel according to claim 6, wherein the first switch
or the second switch is a transistor.
19. The touch panel according to claim 6, wherein the first switch
and the second switch are disposed on a joint portion between the
touch panel and the driver chip.
20. A display device comprising the touch panel according to claim
1.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Chinese
Patent Application No. 201510152694.5, filed with the Chinese
Patent Office on Apr. 1, 2015 and entitled TOUCH PANEL AND DISPLAY
DEVICE", the content of which is incorporated herein by reference
in its entirety.
TECHNICAL FIELD
[0002] The disclosure relates to display technology, and more
particularly to a touch panel and a display device including the
touch panel.
BACKGROUND OF THE INVENTION
[0003] FIG. 1 is a schematic structural diagram of a conventional
touch panel. As shown in FIG. 1, the conventional touch panel
includes a common electrode layer Comm, which is provided with
multiple electrode blocks E insulated from each other, and each of
the electrode blocks E may serve as a common electrode and a touch
electrode, that is, the common electrode doubles (is also used) as
the touch electrode in the conventional touch panel. Each of the
electrode blocks E is connected to a signal line 10, and the signal
line 10 is configured to transmit a common voltage signal and a
touch sensing signal to the electrode block E connected to the
signal line 10 in a time-division manner.
[0004] FIG. 2 is a schematic structural diagram of a circuit for
one pixel unit in one electrode block. An electrode block 200
includes multiple pixel units, and each pixel unit is provided with
a TFT transistor and a pixel electrode. A gate of the TFT
transistor is connected to a gate line G, a source of the TFT
transistor is connected to a data line D, and a drain of the TFT
transistor is connected to the pixel electrode.
[0005] The touch panel with the common electrode doubling as the
touch electrode is driven in a time-division manner, that is, a
display drive operation is performed before a touch drive operation
is performed in one frame.
[0006] In the case that the touch panel is in a display period, the
TFT transistor for controlling the pixel unit is turned on, a data
signal is transmitted to the pixel electrode via the data line D,
and a common voltage signal is transmitted to the electrode block
200 via the signal line 10; and in the case that the touch panel is
in a touch sensing period, a touch sensing signal is transmitted to
the electrode block 200 via the signal line 10. Whether the touch
panel is in the display period or the touch sensing period, a pixel
capacitor comprised of the pixel electrode and the common electrode
is charged. Hence, while the touch panel is operating, there is a
potential difference between the pixel electrode and the common
electrode corresponding to the pixel electrode, and thus the liquid
crystal molecules between the pixel electrode and the common
electrode are twisted with a specific angle. In the case that the
touch screen is suddenly powered off, the pixel capacitor is not
discharged or partially discharged, and thus there is an amount of
residual charge between the pixel electrode and the common
electrode in a long term. The liquid crystal molecules may not be
twisted due to the existence of the residual charge. Furthermore,
some impurity ions in the liquid crystal may be polarized and the
polarized impurity ions may not be twisted due to the presence of
the residual charges, and the polarized impurity ions may be
attached to an upper substrate and a lower substrate of the touch
screen due to the presence of the residual charge in a long term.
Noticeable flickers may occur on a touch screen when the touch
screen is turned on.
BRIEF SUMMARY OF THE INVENTION
[0007] In view of the above, embodiments of the present invention
provide a touch panel that can prevent flickers from occurring on a
touch screen.
[0008] According to the present invention, a touch panel includes a
common electrode and multiple pixel electrodes, and each of the
pixel electrodes is short-circuited to the common electrode in the
case that the touch panel is powered off.
[0009] A display device is further provided according to the
disclosure, and the display device includes a touch panel which
includes a common electrode and multiple pixel electrodes, and each
of the pixel electrodes is short-circuited to the common electrode
in the case that the touch panel is powered off.
[0010] Compared with the conventional touch panel, a touch panel
according to the disclosure has a number of advantages.
[0011] For the touch panel according to the disclosure, each of the
pixel electrodes is short-circuited to the common electrode in the
case that the touch panel is powered off. In this case, after the
touch panel is powered off, there is no potential difference
between the pixel electrode in each pixel unit and the common
electrode, and thus there is no residual charge between the pixel
electrode and the common electrode. Therefore, in the case that the
touch panel is powered off, the liquid crystal molecules may be
twisted and the impurity ions in the liquid crystal may not be
polarized, and may not be attached to an upper substrate and a
lower substrate of a touch screen in a long term. Thus, flickers
may not occur on the touch screen when the touch panel is turned
on. Hence, with the touch panel according to the present invention,
the display device has an improved display effect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In order to understand the technical solutions in the
disclosure more clearly, the following briefly describes the
drawings according to embodiments of the disclosure.
[0013] Apparently, the drawings are only some embodiments of the
present disclosure, and other drawings may be obtained by those
skilled in the art according to those drawings without creative
efforts.
[0014] FIG. 1 is a schematic structural diagram of a conventional
touch panel;
[0015] FIG. 2 is a schematic diagram of operating principle of a
pixel unit in an electrode block;
[0016] FIG. 3 is a schematic structural diagram of a touch panel
according to a first embodiment of the disclosure;
[0017] FIG. 4 is a schematic structural diagram of a touch panel
according to a second embodiment of the disclosure; and
[0018] FIG. 5 is a schematic structural diagram of another touch
panel according to the second embodiment of the disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0019] To make the above object, technical solutions and advantages
of the disclosure more apparent and complete, in the following,
specific embodiments of the disclosure are illustrated in detail in
conjunction with the drawings.
[0020] As described in the background section, one of the reasons
why noticeable flickers occur on the touch screen is that there is
a potential difference between the pixel electrode and the common
electrode corresponding thereto after the touch panel is powered
off. In order to eliminate the potential difference, for the touch
panel according to the disclosure, each of the pixel electrodes is
short-circuited with the common electrode corresponding thereto, in
the case that the touch panel is powered off. Therefore, the
potential difference between each pixel electrode and the common
electrode corresponding thereto is eliminated, and thus flickers
can be prevented from occurring on the touch screen.
[0021] For a conventional touch panel known in the art, the common
electrode doubles as the touch electrode. That is, an electrode may
be used as the common electrode and the touch electrode. The
electrode serves as the common electrode in the case that a common
voltage signal is inputted to the electrode; and the electrode
serves as the touch electrode in the case that a touch drive signal
is inputted to the electrode.
[0022] In order to double the common electrode as the touch
electrode, the conventional art uses a clock pulse signal to drive
the display operation and the touch sensing operation of the touch
screen in a time-division manner.
[0023] For the touch panel with the common electrode doubling as
the touch electrode, the common electrode in the touch panel is
divided into multiple electrode blocks that are insulated from each
other. Each of the electrode blocks serves as a common electrode of
the touch panel in the case that a display signal is inputted to
the electrode block; and each of the electrode blocks serves as a
touch electrode of the touch panel in the case that a touch sensing
signal is inputted to the electrode block.
[0024] Generally, the area of the electrode block is larger than
the area of the pixel unit. Therefore, the region of one electrode
block corresponds to multiple pixel units and the electrode block
is shared by the pixel units. Since each of the pixel units
includes a pixel electrode, one electrode block corresponds to
multiple pixel electrodes. That is, one electrode block is shared
by all pixel electrodes corresponding to the region of the
electrode block, and the shared electrode block serves as a touch
electrode and a common electrode.
[0025] In order to prevent flickers from occurring on the screen
for the touch panel with the common electrode doubling as the touch
electrode, embodiments of the present invention provide a touch
panel.
[0026] The touch panel includes a common electrode and multiple
pixel electrodes, the touch panel includes at least one column of
pixel electrodes, the common electrode includes multiple electrode
blocks insulated from each other, and each of the electrode blocks
corresponds to multiple pixel electrodes and doubles as a touch
electrode.
[0027] The touch panel further includes multiple signal lines and
multiple data lines, each of the signal lines is connected to a
respective electrode block, each of the data lines is connected to
pixel electrodes in a same column, and each of the data lines is
configured to provide data signals for the pixel electrodes in the
same column.
[0028] The data line connected to all pixel electrodes
corresponding to an electrode block is short-circuited to the
signal line connected to the electrode block, in the case that the
touch panel is powered off.
[0029] Since the data line is configured to provide the data
signals for the pixel electrodes, the data line is electrically
connected to the pixel electrodes. The signal line is configured to
provide a common voltage signal or a touch sensing signal for the
electrode block, and the signal line is electrically connected to
the electrode block. Therefore, in the case that the touch panel is
power off, a short-circuit connection between the data line
configured to provide data signals to all pixel electrodes
corresponding to an electrode block and the signal line connected
to the electrode block, is equivalent to, short-circuit connections
between all the pixel electrodes corresponding to the electrode
block and the common electrode corresponding to the pixel
electrodes.
[0030] It should be noted that, the case that the touch panel is
powered off according to the embodiments of the disclosure refers
to the case that a driver chip for providing drive signals for the
touch panel is powered off, and the whole touch panel is in a
non-operating state.
[0031] In the case that the touch panel is powered off, there is no
potential difference between all pixel electrodes corresponding to
each of the touch electrodes and the common electrode corresponding
to the pixel electrodes. There is no potential difference between
the pixel electrode in each pixel unit and the common electrode in
the touch panel and thus there is no residual charge between the
pixel electrode and the common electrode, after the touch panel is
powered off. Therefore, in the case that the touch panel is powered
off, the liquid crystal molecules may be twisted and the impurity
ions in the liquid crystal may not be polarized, and may not be
attached to an upper substrate and a lower substrate of the touch
screen in a long term, and thus flickers may not occur on the touch
screen when the touch panel is turned on.
[0032] In another embodiment of the disclosure, a short-circuit
connection between all the data lines and all the signal lines in
the touch panel is established, in the case that the touch panel is
powered off. In this case, electric potentials of the pixel
electrodes in all the pixel units and the common electrodes, in the
touch panel, are equal. Compared with the above embodiment in which
electric potentials of the pixel electrodes in all pixel units are
equal to that of the common electrode, for each of the electrode
blocks, a charge migration speed is slower and thus a change speed
of potential difference is slower in the embodiment in which the
electric potentials of the pixel electrodes in all pixel units and
the electric potentials of the common electrodes, in the touch
panel, are all equal.
[0033] It should be further noted that, in order to reduce the
parasitic capacitance between the signal lines, extension
directions of the data lines are the same as those of the signal
lines, and the extension directions may be the column directions of
the pixel electrode array.
[0034] In order to understand how to short-circuit each of the
pixel electrodes with the common electrode for the touch panel
according to the disclosure in the case that the touch panel is
powered off more clearly, hereinafter a touch panel with one touch
electrode is taken as an example for illustration.
First Embodiment
[0035] FIG. 3 is a schematic structural diagram of a touch panel
including one electrode block. An electrode block 100 is disposed
to correspond to multiple pixel electrodes (not shown in FIG. 3) in
two columns of pixel electrodes, and thus the electrode block 100
corresponds to two data lines d1 and d2, and a signal line s is
connected to the electrode block 100. The signal line s is
configured to input a common voltage signal or a touch sensing
signal to the electrode block 100 in a time-division manner, and
the two data lines dl and d2 are configured to input display
signals to the two columns of pixel electrodes connected to the two
data lines dl and d2 respectively in the display period. It should
be noted that, the signal line s may be disposed in a different
layer from the electrode block 100, or may be disposed in the same
layer with the electrode block 100. In the case that the signal
line s is disposed in a different layer from the electrode block
100, the signal line s is electrically connected to the electrode
block 100 through a via hole.
[0036] As shown in FIG. 3, the touch panel includes the electrode
block 100, two columns of pixel electrodes (not shown in FIG. 3)
corresponding to the region of the electrode block 100, the two
columns of pixel electrodes correspond to the two data lines d1 and
d2 respectively, and each of the data lines is connected to the
respective column of pixel electrodes.
[0037] In order to control the pixel electrode to be
short-circuited with (to) the common electrode corresponding to the
pixel electrode in the case that the touch panel is powered off,
the touch panel further includes two first switches SW1a and SW1b,
a second switch SW2, a control line C and a short-circuit line S.
The first switches SW1a and SW1b are connected to the data lines d1
and d2 respectively, and the second switch SW2 is connected to the
signal line s.
[0038] The first switches and the second switch each include a
control electrode, a first electrode and a second electrode. The
control electrodes of the first switches SW1a and SW1b and the
control electrode of the second switch SW2 are connected to the
control line C, the control line C is configured to transmit a
control signal, and the control signal is configured to control the
first switches SW1a and SW1b and the second switch SW2 to be turned
off in the case that the touch panel operates, or to be turned on
in the case that the touch panel is powered off; that is, the
control signal is a pulse signal and controls the first switches
SW1a and SW1b and the second switch SW2 to be turned off in the
case that the touch panel operates, or to be turned on in the case
that the touch panel is powered off.
[0039] It should be further noted that, the control signal may be
provided by a driver chip outside the touch panel. In this case, an
input terminal of the control line is connected to an output
terminal of the driver chip.
[0040] The first electrode of the first switch SW1a is connected to
the data line d1, the first electrode of the first switch SW1b is
connected to the data line d2, and the first electrode of the
second switch SW2 is connected to the signal line s.
[0041] The second electrodes of the first switches SW1a and SW1b
are connected to the second electrode of the second switch SW2;
that is, in the embodiment, the second electrodes of the first
switches are connected to the second electrode of the second switch
via the short-circuited line S, where the first electrodes of the
first switches are connected to the data lines connected to all
pixel electrodes corresponding to the electrode block, and the
first electrode of the second switch is connected to the signal
line connected to the electrode block. In this case, there is no
potential difference between all the pixel electrodes corresponding
to the electrode block and the common electrode corresponding to
the pixel electrodes, in the case that the touch panel is powered
off. In a specific embodiment of the disclosure, the short-circuit
line may be in a floating state or may be connected to a stable
voltage level. The potential difference between the pixel
electrodes in the electrode block and the common electrode
corresponding to the pixel electrodes may be equal to zero
regardless of whether the short-circuit line is floating or at a
stable voltage level.
[0042] In the embodiment of the disclosure, the second electrodes
of the first switches SW1a and SW1b are short-circuited with (to)
the second electrode of the second switch SW2. The first electrodes
of the first switches SW1a and SW1b are connected to the data lines
d1 and d2 respectively, the first electrode of the second switch
SW2 is connected to the signal line s, and the second electrodes
are short-circuited with (to) each other. Therefore, the data lines
d1 and d2 are short-circuited with (to) the signal line s after the
first switches and the second switch are turned on, and thus there
is no potential difference between the pixel electrodes and the
common electrode.
[0043] In a specific embodiment of the disclosure, the first
switches and/or the second switch described above may be any
electronic switch, such as a transmission gate. In another specific
embodiment of the disclosure, the first switch and/or the second
switch described above may alternatively be a transistor. The
transistor may be a thin film transistor, the control electrode is
a gate, and the second electrode is a drain in the case that the
first electrode is a source, or the second electrode is a source in
the case that the first electrode is a drain. Additionally, the
transistor may further be an MOS transistor, the control electrode
is a gate, and the second electrode is a drain in the case that the
first electrode is a source, or the second electrode is a source in
the case that the first electrode is a drain.
[0044] The first switch and/or the second switch are disposed in a
region where a connection between the touch panel and the driver
chip outside the touch panel is established. In a specific
embodiment of the disclosure, the first switch and the second
switch are disposed on a step of the joint (a joint portion)
between the touch panel and the driver chip. It should be noted
that the step (joint portion) is disposed inside the touch
panel.
[0045] The schematic structural diagram of the touch panel
according to the embodiment of the disclosure is described above.
With the touch panel according to the embodiment, there is no
potential difference between the pixel electrodes and the common
electrode corresponding to the pixel electrodes in the case that
the touch panel is powered off, and thus flickers can be prevented
from occurring on the touch screen.
[0046] It should be noted that, the touch panel according to the
embodiment of the disclosure is controlled as follows. The
operating periods of the touch panel include a display period and a
touch sensing period. The first switch and the second switch are
both in off-state, i.e., they are turned off by a pulse control
signal transmitted to the control line C. In this case, the touch
panel operates normally. In the case that the touch panel is
powered off, the pulse control signal transmitted to the control
line C turns on the first switch and the second switch, and thus
the data lines for providing the data signals to all pixel
electrodes corresponding to the electrode block is connected to the
signal line connected to the electrode block, and there is no
potential difference between all pixel electrodes corresponding to
the touch electrode and the touch electrode. Since the common
electrode doubles as the touch electrode, there is no potential
difference between all pixel electrodes corresponding to the touch
electrode and the common electrode. After the touch panel is
powered off, there is no residual charge between the pixel
electrodes and the common electrode. Therefore, in the case that
the touch panel is powered off, the liquid crystal molecules may be
twisted and the impurity ions in the liquid crystal may not be
polarized, and may not be attached to an upper substrate and a
lower substrate of a touch screen in a long term, and thus flickers
is avoided from occurring on the touch screen.
[0047] It should be noted that, the schematic structural diagram of
the touch panel shown in FIG. 3 only illustrates a structure of the
touch panel related to improvements in the touch panel according to
the disclosure, and does not illustrate a structure not tightly
related to the improvements in the touch panel according to the
disclosure, but it should not be understood that the touch panel
does not include the structure not tightly related to the
improvements in the touch panel according to the disclosure. In
practice, pixel electrodes and a thin film transistor for
controlling the pixel electrodes are disposed above or below the
region of each electrode block in the touch panel, which is not an
improvement in the touch panel according to the disclosure, and is
not shown in FIG. 3, for simplicity.
[0048] According to the first embodiment, the structure of the
touch panel including one electrode block is illustrated. In the
following, a structure of a touch panel including multiple
electrode blocks is illustrated according to a second
embodiment.
Second Embodiment
[0049] FIG. 4 is a schematic structural diagram of a touch panel
according to the second embodiment of the disclosure. As shown in
FIG. 4, the touch panel according to the embodiment of the
disclosure includes four electrode blocks 401 to 404, data lines d1
to d4, and signal lines s1 to s4 connected to the electrode blocks
401 to 404 respectively.
[0050] In order to control the pixel electrode to be
short-circuited with the common electrode in the case that the
touch panel is powered off, the touch panel shown in FIG. 4 further
includes four first switches SW1a, SW1b, SW1c and SW1d, four second
switches SW2a, SW2b, SW2c and SW2d, a first short-circuited line
S1, a second short-circuited line S2, and a control line C. The
four first switches SW1a, SW1b, SW1c and SW1d are connected to the
data lines d1, d2, d3, and d4 respectively, and the four second
switches SW2a, SW2b, SW2c and SW2d are connected to the signal
lines s1, s2, s3, and s4 respectively.
[0051] The first switches SW1a, SW1b, SW1c and SW1d and the second
switches SW2a, SW2b, SW2c and SW2d each include a control
electrode, a first electrode and a second electrode. The control
electrodes of the first switches SW1a, SW1b, SW1c and SW1d and the
control electrodes of the second switches SW2a, SW2b, SW2c and SW2d
are connected to the control line C, the control line C is
configured to transmit a control signal, and the control signal is
configured to control the first switches SW1a, SW1b, SW1c and SW1d
and the second switches SW2a, SW2b, SW2c and SW2d to be turned off
in the case that the touch panel operates, or to be turned on in
the case that the touch panel is powered off; that is, the control
signal is a pulse signal, where a low level signal is unable to
turn on the first switches SW1a, SW1b, SW1c and SW1d and the second
switches SW2a, SW2b, SW2c and SW2d, and thus the first switches
SW1a, SW1b, SW1c and SW1d and the second switches SW2a, SW2b, SW2c
and SW2d are in off-state in the case that the touch panel
operates, or the control signal can turn on the first switches
SW1a, SW1b, SW1c and SW1d and the second switches SW2a, SW2b, SW2c
and SW2d in the case that the touch panel is powered off.
[0052] It should be further noted that, the control signal may be
provided by a driver chip outside the touch panel.
[0053] The first electrodes of the four first switches SW1a, SW1b,
SW1c and SW1d are connected to the data lines d1 to d4
respectively, and the first electrodes of the second switches SW2a,
SW2b, SW2c and SW2d are connected to the signal lines s1, s2, s3,
and s4 respectively.
[0054] The second electrodes of the first switches are connected to
the second electrodes of the second switches respectively via the
short-circuited lines, where the first electrode of each second
switch is connected to a signal line connected to an electrode
block, and the first electrodes of respective first switches are
connected to the data lines connected to all pixel electrodes
corresponding to the same electrode block. In this case, there is
no potential difference between all the pixel electrodes
corresponding to one of the electrode blocks and the common
electrode corresponding to the pixel electrodes, in the case that
the touch panel is powered off. In a specific embodiment of the
disclosure, the short-circuited line may be floated or may be
connected to a stable level. The above potential difference may be
equal to zero by any one of such two ways.
[0055] It should be noted that, the data line d1 and the data line
d2 are configured to transmit data signals to the pixel electrodes
corresponding to the regions of the electrode blocks 401 and 403.
Similarly, the data line d3 and the data line d4 are configured to
transmit data signals to the pixel electrodes corresponding to the
regions of the electrode blocks 402 and 404.
[0056] In the embodiment of the disclosure, the second electrodes
of the first switches SW1a and SW1b are short-circuited with the
second electrode of the second switch SW2a, and the second
electrodes of the first switches SW1a and SW1b are short-circuited
with the second electrode of the second switch SW2b. That is, the
second electrodes of the first switches SW1a and SW1b are connected
to the second electrodes of the second switches SW2a and SW2b via
the first short-circuited line S1; similarly, the second electrodes
of the first switches SW1c and SW1d are connected to the second
electrodes of the second switches SW2c and SW2d via the second
short-circuited line S2.
[0057] The schematic structural diagram of the touch panel
according to the embodiment of the disclosure is described above.
With the touch panel according to the embodiment, there is no
potential difference between the pixel electrode and the common
electrode corresponding to the pixel electrode in the case that the
touch panel is powered off, and thus flickers may be avoided from
occurring on the touch screen.
[0058] It should be noted that, only four electrode blocks are
illustrated in the touch panel shown in FIG. 4. In practice, much
more than four electrode blocks are included in the touch panel.
Structures of a touch panel including more than four electrode
blocks and a touch panel including less than four electrode blocks
may be obtained by those skilled in the art without creative
efforts, based on the structure of the touch panel shown in FIG. 4.
These structures of the touch panel all fall into the scope of the
disclosure.
[0059] The number of the data lines corresponding to the region of
one electrode block is not defined herein. Two data lines as shown
in FIG. 3 are only exemplary. In practice, the number of the data
lines corresponding to the region of one electrode block may be any
integer in the embodiments of the disclosure.
[0060] As an extension of the above embodiments, in the case that
the electrode block array is an array including N rows and M
columns of electrode blocks, where N and M are positive integers,
the extension directions of a signal line connected to each
electrode block and the data lines for providing data signals for
the pixel electrodes are set to be column directions of the
electrode block array. The region of any one column of the
electrode blocks corresponds to h columns of pixel electrodes,
where h is a positive integer, and thus there are h data lines for
providing data signals for the h columns of pixel electrodes in the
region of the electrode blocks in one column. For one column of the
electrode blocks, N signal lines are needed to be respectively
connected to each electrode block in the one column of the
electrode blocks, and thus h first switches and N second switches
are needed. The control electrodes of the h first switches and the
control electrodes of N second switches are connected to the
control line, the first electrodes of the h first switches are
connected to the data lines respectively, and the first electrodes
of the N second switches are connected to the signal lines
respectively. The second electrodes of the h first switches are
connected to the second electrodes of N second switches via the
short-circuited line.
[0061] For the touch panel according to the above second
embodiment, the extension directions of the data lines and the
signal lines are the column directions of the electrode block
array. It can be understood that, the extension directions of the
data lines and the signal lines are the row directions of the
electrode block array, as a variation of the embodiment of the
disclosure.
[0062] In the touch panel according to the above embodiments, the
second electrodes of the first switches are electrically connected
to the second electrodes of the second switches respectively, where
the first electrode of each second switch is connected to a signal
line connected to an electrode block in a column of electrode
blocks, and the first electrodes of the respective first switches
are connected to the data lines connected to all pixel electrodes
corresponding to the same electrode block or the same column of
electrode blocks. By using such connection way, charge migration
speeds in the pixel electrodes and the common electrode are fast,
and the pixel capacitor can be discharged in a short period of
time, and has a high discharge efficiency.
[0063] In an alternative solution of the above embodiment, as shown
in FIG. 5, the second electrodes of all first switches in the touch
panel may be electrically connected to the second electrodes of all
second switches in the touch panel via a short-circuited line S.
Therefore, the potential differences between each pixel electrode
and the common electrode in the touch panel are equal.
[0064] It should be noted that, the structure of the touch panel
shown in FIG. 5 is obtained by changing the structure of the touch
panel shown in FIG. 4 slightly. The change is that the second
electrodes of the switches (including the first switch and the
second switch) corresponding to different columns of the electrode
blocks are connected, and thus an electric connection among the
second electrodes of all first switches and the second electrodes
of all second switches in the touch panel is achieved.
[0065] Based on the touch panel according to the first embodiment
or the second embodiment described above, a display device is
further provided according to the embodiment of the disclosure. The
display device includes the touch panel according to any one of the
above embodiments. The display device may be a mobile phone, a
computer and a wearable electronic device with a display
function.
[0066] The description of the embodiments disclosed herein enables
those skilled in the art to implement or use the present
disclosure. Various modifications to the embodiments are obvious to
those skilled in the art, and the general principle herein can be
implemented in other embodiments without deviation from the spirit
or scope of the present disclosure. Therefore, the present
disclosure is not limited to the embodiments described herein, but
conforms to the widest scope consistent with the principle and
novel features disclosed herein.
* * * * *